关键词: 农业非点源污染, 输出系数法, 时空分布, 入河系数, 仙桃市,

Abstract: In order to investigate the temporal and spatial distributional characteristics of agricultural non-point source pollution load in Xiantao City, Hubei Province, the amounts of load of the total nitrogen(TN) and total phosphorus(TP) of non-point source pollution in Xiantao city from 2010 to 2017 were estimated by the modified export coefficient method and taking account of the precipitation factor, slope factor and coefficient of entering river. And the spatial distribution of the agricultural non-point source pollution load of every town was drawn by ArcGIS10.3.1. The results showed that the inter-annual variation of TN and TP pollution loads were significantly affected by annual rainfall and various types of agricultural pollution sources. The annual average amounts of TN and TP were 1959.6 t/a and 249.1 t/a respectively. The contribution rank of various types of pollutant sources to TN was as follow: agricultural land > freshwater aquaculture > livestock and poultry breeding > rural living for TN load, and to TP load was: agricultural land > livestock and poultry breeding > freshwater aquaculture > rural living. The most serious areas of non-point source pollution were mainly distributed in the eastern areas of Xiantao city, such as Xiliuhe, Changtangkou and Yanglinwei town, which were the key areas for prevention and control of agricultural non-point source pollution.

Key words: agricultural non-point source pollution, export coefficient method, spatial-temporal distribution, coefficient of entering river, Xiantao City